Organizations use videoconferencing systems to conduct meetings. Some rudimentary videoconferencing systems include one or two screens and videoconferencing equipment. However, organizations continually desire to make videoconferences more interactive and effective.
One way to achieve interactive videoconferences involves building a meeting room equipped with specifically designed displays, cameras, microphones, and tables. This type of videoconferencing system requires a great deal of space and capital investment to build. Examples of this type of videoconferencing system include the Polycom® RealPresence™ Experience High Definition (RPX™ HD) system.
In the RPX™ HD systems, for example, a specially designed suite is constructed to accommodate anywhere from 4 to 28 participants. The custom suite is fitted with specific furniture, chairs, a ceiling cloud of acoustic baffling, studio lighting, a sound paneling back wall, videoconferencing equipment, ceiling microphones, and a full-screen video display (8′×42″ or 16′×42″). Other telepresence systems include the Polycom® Open Telepresence Experience™ (Polycom OTX™) solution, which has a set of integrated displays and cameras connected directly to a table for participants.
Current videoconferencing systems are at best configured for stereo audio using stereo loudspeakers. Because the systems use microphones in proximity to the loudspeakers, the system relies on echo cancellation of the stereo audio to handle any acoustic coupling of the far-end audio that is output by the loudspeakers and is being picked up by the local microphones to prevent that echo audio from being sent back to the far-end. Such echo is distracting so that current videoconferencing systems are configured to, and are at best mainly capable of, handling echo cancellation in stereo environments, but not more complicated environments.
Stereo loudspeakers have been used on the left and right sides of the set of displays in the telepresence system. Using stereo loudspeakers in these locations, however, does not work well due to the large seating area that telepresence systems' have. Most listeners are seated outside of the stereo “sweet spot” of the loudspeakers and simply perceive the talker's voice as coming only from the nearest loudspeaker (i.e., at the left or right edge of the set of displays).
Rather than positioning the loudspeakers at the sides of the displays, telepresence systems in the past have had loudspeakers placed either above the display or below display. When LCD screens or the like are used, for example, the loudspeakers are located at the edges of the displays (or farther away). The resulting distance between a talker's audio location and the video image of the talker can seem unnatural and can diminish the interactive feel of the multi-display telepresence system. For this reason, creating the illusion that speech is coming from the center of an electronic display (where loudspeakers cannot be located) can be difficult.
As long as smaller displays are used, there is not very much displacement between the loudspeaker and the center of the display's screen so listeners do not find the offset of the loudspeaker's output and the video image of the talker to be noticeable or objectionable. As taller screens are being used in telepresence systems, the vertical displacement between the image of the talker on the screen and the apparent location of the talker's voice increases, making the resulting experience more objectionable and unnatural.
The subject matter of the present disclosure is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.